06-03-2019, 11:02 PM
That's what I did. 1/4" brass domed slotted head screw. Took my time. Applied valve lapping compound to both parts, moderate pressure while spinning somewhat slower with a drill while swirling or orbiting the drill and screw so the screw wouldn't wear all in one spot. Wipe clean, check progress and repeat until desired crown depth is achieved. I went about 3x depth radially compared to the barrel's groove depth. I used two screws. The first I used mostly and it ended up wearing to an odd shape. Once I was close to the depth I wanted I switched to the other screw for the "finishing" passes where I used less pressure. I did notice a little burr when I was done but I'm pretty sure that shot out after a handful of rounds. I think less heat (less pressure and slower speed) would keep the burr down.